Biology 101 - The Basis of Life

Brendan frequently comes home from soccer practice with muddy socks. Previous pretreatment techniques (such as presoaking in bleach) have not worked to remove the stains. Brendan had heard about a new product that was advertised to completely remove mud stains by pretreating with the product for 24 hours. Brendan was tired of wearing stained socks and hypothesized that the new product would get the mud stains out of his soccer socks. Which statement describes the best experimental design to test the new product's effectiveness? a. Test old socks, stained previously, by pretreating one sock for 24 hours while leaving the other sock untreated. b. Test new socks, worn once to soccer, by pretreating one sock for 24 hours while leaving the other sock untreated. c. Test new shorts and T‑shirt, worn to soccer, by pretreating the T‑shirt for 24 hours while leaving the shorts untreated. d. Test new socks, worn once to soccer, by pretreating one sock first with bleach and then new product for 24 hours while leaving the other sock untreated. Which example represents the control for Brendan's experiment? a. untreated shorts b. pretreated new sock c. untreated new sock d. pretreated old sock

#1 b. Test new socks, worn once to soccer, by pretreating one sock for 24 hours while leaving the other sock untreated. #2 c. untreated new sock

Jenna, an ornithologist, is interested in morphological variation in Clark's Nutcracker (Nucifraga columbiana). She is studying a museum collection of Clark's Nutcrackers for the contribution of variation between different ages and sexes. Determine the order in which Jenna plans and implements a comparative investigation. Rank the steps in the order in which they should occur in a scientific investigation. The first step should be placed in the highest position, at step 1, and the last step should be placed in the lowest position, at step 6.

1. Jenna reads background information on Clark's Nutcrackers and on other similar studies 2. Jenna develops a scientific hypothesis and designs an investigation to test it. 3. Jenna takes measurements, such as mass, tail length, beak length, and sex, and records the data. 4. Jenna analyzes the data. 5. Jenna concludes that variation is highest among juveniles and that males are larger than females. 6. Jenna publishes the results and conclusions in scientific journal.

Ashley hypothesizes that adding coffee grounds to the soil will help the plants grow faster. She designs a controlled experiment to determine if this hypothesis is supported. She grows one group of soybean seedlings under normal conditions. She mixes three tablespoons of coffee grounds into the soil of the second group and grows the seedlings under the same light, temperature, and watering regimen. After three weeks, she measures the height of the seedlings and compares the two groups. Identify the parts of the experiment. Place only one term in each category. You will not place all the terms. Would it be a good experimental design if she also, as part of the same experiment, tests seedling growth at different temperatures by growing one group at 20 ∘C20 ∘C (68 ∘F)(68 ∘F) and the other group at 25 ∘C25 ∘C (77 ∘F)?(77 ∘F)? a. Yes, it would enable her to compare more than one environmental factor at a time. b. Yes, but it is not necessary to grow one group without coffee since that is not being tested. c. No, the other conditions should remain the same for the experiment to be scientifically sound. d. No, a temperature difference of 5 ∘C5 ∘C is not large enough to detect a significant temperature effect.

Experimental group: Seedlings grown with coffee grounds Control group: Seedlings grown without coffee grounds Dependent variable: Seedling height Independent variable: Soil #2 - c. No, the other conditions should remain the same for the experiment to be scientifically sound.

In a 50 square mile section of forest, there are some cut patches of forest where the trees have been removed and some patches of forest that have been left uncut. Birds are nesting in both cut and uncut forest patches. Beginning with the first step, place the steps in sequence for an investigation of the nesting birds using the scientific method.

First Step of Investigation 1. Observe birds nesting in cut patches and uncut patches of forest. 2. Hypothesize that more birds nest in cut forest patches. 3. Develop a plan for conducting nest counts in several similarly sized patches of cut and uncut forest. 4. Count the number of nests found and record the data. 5. Compare the data collected concerning nests from cut and uncut patches of forest. 6. Determine whether more birds nests in cut or uncut forest patches and share this conclusion with other researchers.

Consider the steps involved in an experiment that uses the scientific method. Arrange the six given steps in the order in which they occur. One of the steps will not be used.

First Step of investigation: 1. After observing a natural phenomenon, develop a question based on the observations. 2. Form a hypothesis that can answer the question about the natural phenomenon. 3. Design an experiment that tests the hypothesis. 4. Conduct the experiment and collect the resulting data. 5. analyze the data collected in the experiment 6. Share the results and conclusions of the experiment.

Sort the statements based on whether they describe a scientific hypothesis or a scientific theory.

Hypothesis: - A researcher suggests an untested explanation that attempts to explain something he or she observed. - Researchers notice that plants growing in iron-rich soil seem to tolerate cold quite well. They plan an experiment to see if iron in the soil improves cold tolerance in plants. - An ornithologist suspects that more young birds will survive in years when caterpillars are an abundant food source. Theory: - Researchers agree on the best explanation that science can offer based on the results of numerous reliable studies Based on overwhelming evidence, researchers conclude the infection disease is spread by microorganisms.

A great variety of predictions and hypotheses can be tested using the methods of science. Even so, there are some questions that do not lend themselves to scientific testing. Classify the statements as predictions or hypotheses that are scientifically testable and those that cannot be tested scientifically.

Scientifically Testable: - Planting fields with several types of rice results in less disease and higher yields - Taking vitamin C supplements every day will decrease the likelihood of catching a cold. - Meditating daily reduces the recurrence of depression in those who have had depression before. Cannot be tested scientifically: - Strawberries taste better when the plants are watered every other day - Using torture to interrogate prisoners is wrong even if the information gained through torture saves lives. - A person's soul is separate from his or her body, and the soul will continue to exist even after the person dies.

Which of these studies has the least to do with legitimate scientific investigation? a. a study to determine whether evolutionary biology should be taught in elementary parochial schools b. a study to examine the relationship between the number of hours spent studying and student test scores c. a study to understand what the effect of being a part of a high school championship baseball team has on college academic performance d. a study to determine whether air quality in a school affects student performance e. a study to examine the effect of using seventh-grade reading material on fifth-grade students' reading comprehension

a study to determine whether evolutionary biology should be taught in elementary parochial schools

Applying your knowledge of the scientific method, which statement best explains the contrast between a hypothesis and theory? a. A hypothesis attempts to explain natural phenomenon and can be tested through experimentation; a theory attempts to summarize a large expanse of natural phenomena and has already been tested thoroughly without contradictory results. b. A hypothesis is made based on limited initial observations; a theory is made based on limited observations made later. c. A hypothesis cannot be disproven through experiment; a theory can be disproven through experiments. d. A hypothesis is easy to make; theories are difficult to make. e. A hypothesis leads scientists to develop experiments; a theory leads scientists to form opinions.

a. A hypothesis attempts to explain natural phenomenon and can be tested through experimentation; a theory attempts to summarize a large expanse of natural phenomena and has already been tested thoroughly without contradictory results.

Which of the statements are examples of a correlation? a. An increase in temperature and an increase in the amount of bottled water sold b. Students who participate more in class and higher grades on exams c. A person's age and a person's ethnicity d. An increase in humidity and the distance between two cities

a. An increase in temperature and an increase in the amount of bottled water sold b. Students who participate more in class and higher grades on exams

Which statement is true? a. Charles Lyell argued that geological forces had gradually shaped the Earth and continued to do so. b. Charles Darwin calculated that the Earth was more than 75,000 years old. c. Thomas Malthus suggested that all species were not created at the same time. d. Georges Cuvier suggested that the Earth was much older than previously believed e. Georges-Louis Leclerc documented fossil discoveries in the 1790s and showed that extinction had occurred.

a. Charles Lyell argued that geological forces had gradually shaped the Earth and continued to do so.

What type of evidence most increases our confidence in experimental results? a. Three different scientists do three different studies, all with the same result b. A scientist runs her experiments 10 times, all with the same result. c. A scientist only runs her experiments twice. d. A scientist observes that two variables appear to be linked. e. Three different scientists do three different studies, investigating different variables and hypotheses.

a. Three different scientists do three different studies, all with the same result

Natural selection is most closely related to: a. differential reproductive success. b. diploidy. c. genetic drift. d. non-random mating. e. gene flow.

a. differential reproductive success.

Which of the statements are examples of hypotheses? a. A scientist concludes that black-peppered moths became common through natural selection. b. A scientist proposes that birds will eat more black-bodied moths than white-bodied moths in a forest unpolluted with soot. c. A scientist predicts that birds will eat more white-bodied moths than black-bodied moths in a forest polluted with soot from factories. d. A scientist observes that peppered moths can exist either as a black-bodied or a white-bodied variety.

b. A scientist proposes that birds will eat more black-bodied moths than white-bodied moths in a forest unpolluted with soot. c. A scientist predicts that birds will eat more white-bodied moths than black-bodied moths in a forest polluted with soot from factories.

Which of the following qualifies as a randomized, double-blind, controlled experimental study? a. A total of 50 men and women of various ages are each given a candy bar with real sugar, 50 men and women of various ages are each given a candy bar with artificial sweetener, and 50 men and women of various ages are not given a candy bar. The people are then observed for signs of sleepiness. The scientist knows what people did or did not eat, but the subjects do not know this information. b. A total of 50 men and women of various ages are each given a candy bar with real sugar, 50 men and women of various ages are each given a candy bar with artificial sweetener, and 50 men and women of various ages are not given a candy bar. The people are then observed for signs of sleepiness. The subjects know which type of candy they ate, but the observing scientist does not. c. A total of 50 men and women of various ages are each given a candy bar with real sugar, 50 men and women of various ages are each given a candy bar with artificial sweetener, and 50 men and women of various ages are not given a candy bar. The people are then observed for signs of sleepiness. No one (the scientist, the observer, and the subjects) knows what type of candy bar was eaten, if any. d. A total of 50 men and women of various ages are each given a candy bar with real sugar. The people are then observed for signs of sleepiness. The scientist knows which candy bar type the people ate, but the subjects do not know this information. e. A total of 50 men (who are 35 years old) are each given a candy bar with real sugar, 50 women (who are 35 years old) are each given a candy bar with artificial sweetener, and 50 men and women (who are 35 years old) are not given a candy bar. The people are then observed for signs of sleepiness. Neither the scientist nor the observer knows what type of candy bar the subjects ate, if any.

c. A total of 50 men and women of various ages are each given a candy bar with real sugar, 50 men and women of various ages are each given a candy bar with artificial sweetener, and 50 men and women of various ages are not given a candy bar. The people are then observed for signs of sleepiness. No one (the scientist, the observer, and the subjects) knows what type of candy bar was eaten, if any.

Many would argue that both the theory of evolution and creationism are equally probable because, after all, they are both theories. What distinction (if any) is there between a scientific theory and a conceptual one that might lead you to disagree with this argument? a. A scientific theory is based on an observer's perception of his or her surroundings. b. A scientific theory is based on many observations that prove it is correct. c. Both of these types of theories involve a degree of faith. d. A scientific theory is supported by testable and reproducible data. e. A scientific theory is always right.

d. A scientific theory is supported by testable and reproducible data.

During an experiment to determine if people with more symmetrical body features have a lower incidence of disease, a researcher first measures the length of several bones in the subject's hands and arms. The device used to measure length does not display a readout of the measurement taken. Instead, a wire connects the measuring device to a computer that records the data. The computer monitor is kept out of sight of the subject and the researcher. Why is such an elaborate device used? a. so that the identity of the subject will remain anonymous b. so that the experiment will be repeatable c. so that the subject will not be injured by the experiment d. so that the measurements are not biased by the researcher e. so that the subject will not know if he or she is part of the control group

d. so that the measurements are not biased by the researcher

An irrational belief that actions or circumstances that are not logically related to a course of events can influence an outcome is called a: a. placebo. b. variable. c. treatment. d. superstition. e. null hypothesis.

d. superstition.

Which of the following is a way that visual displays of data can potentially mislead readers? a. representation of a dependent variable on the y-axis b. presenting the relationship between two variables c. use of known sources of data d. use of ambiguity in labeling e. use of a pie chart to compare data as a proportion of the whole

d. use of ambiguity in labeling

A population is: a. a group of individuals of the same species that have the potential to interbreed. b. a group of individuals of the same species that live in the same general location and have the same genotypes. c. always clearly defined. d. a group of species that share the same habitat. e. a group of individuals of the same species that live in the same general location and have the potential to interbreed.

e. a group of individuals of the same species that live in the same general location and have the potential to interbreed.

A fossil is defined most broadly as: a. the process of preservation of intact animal bodies. b. the preserved bones of vertebrates. c. a piece of an organism that has turned into rock. d. the preserved pieces of hard parts (e.g., shell or bone) of extinct animals. e. any preserved remnant or trace of an organism from the past.

e. any preserved remnant or trace of an organism from the past.

A "controlled" experiment occurs when: a. participants are randomly sampled from various socio-demographic backgrounds, increasing the generalizability of the results. b. neither the researcher nor the participant know whether the participant is in the treatment or control group. c. the control group receives nothing. d. participants are randomly distributed into treatment or control groups. e. groups are kept as similar as possible and are treated identically, except for the variable of interest.

e. groups are kept as similar as possible and are treated identically, except for the variable of interest.

The scientific method: a. can only be used to understand scientific phenomena. b. could be used to prove or disprove the existence of God. c. is a rigid, linear set of steps that must be followed exactly, every time a critical experiment is conducted. d. can appear to reveal links between two phenomena that do not actually exist. e. is a deductive process based on testable and measurable events.

e. is a deductive process based on testable and measurable events.

According to Darwin's theories and observations on "the struggle for existence," organisms better suited to an environment have a greater probability of surviving and will also: a. be faster runners. b. have fewer predators. c. lead long, satisfying lives. d. have larger bodies. e. leave more offspring.

e. leave more offspring.

If you conduct an experiment that rejects your hypothesis, then: a. your experiment was a failure. b. your experiment was poorly designed. c. you are less likely to get funding for your next experiment. d. you should publish your results anyway. e. the null hypothesis was a better fit to your data.

e. the null hypothesis was a better fit to your data.

Which statement is the best description of evolution as currently understood by modern biologists? a. Evolution is influenced by the differential survival and reproduction of phenotypes. b. Evolution includes the results of selection for acquired characteristics. c. Evolution is synonymous with the process of mutation. d. Evolution is synonymous with the process of gene flow. e. Evolution is goal directed.

a. Evolution is influenced by the differential survival and reproduction of phenotypes.

In 2001, the journal Behavioral Ecology changed its policy for reviewing manuscripts submitted for publication. Its new policy instituted a double‑blind process, whereby neither the reviewers' nor the authors' identities were revealed. An analysis of papers published between 1997 and 2005 revealed that after the double‑blind policy took effect the number of published papers in which the first author was female increased significantly, but not to the expected 50%. Placeholder Art. Two pie charts show the percentage of papers published with a female first author. The first pie chart shows when reviewers knew the sex of the author and has a slice that is a 23 point of 7 percent of the pie. The second pie chart shows the reviewers did not know the sex of the author and has a slide that is 31 point 6 percent of the whole. Select possible explanations for why 50% of the papers published between 1997 and 2005 were not written by female authors, even after the change in the review policy. a. Reviewers determined sex bias from other correlating factors, such as academic institution or writing style. b. Female scientists were less likely to author papers than their male counterparts during this timeframe. c. Female scientists authored a lower percentage of submitted papers than male authors from 1997 to 2005. d. Female scientists were less likely to study subjects covered by this particular journal than male scientists.

a. Reviewers determined sex bias from other correlating factors, such as academic institution or writing style. c. Female scientists authored a lower percentage of submitted papers than male authors from 1997 to 2005.

Which example describes a hypothesis? a. a falsifiable suggested explanation for a particular phenomenon or set of observations b. a process by which scientists investigate a natural phenomenon or group of observations to accurately explain how the natural world works c. an established explanation for a phenomenon or group of observations that is testable and is well‑supported by evidence d. a proposed explanation for a phenomenon that cannot be tested for supporting evidence or falsified

a. a falsifiable suggested explanation for a particular phenomenon or set of observations

"Scientists can never observe evolution in action." This statement is: a. false. Multiple replicated, controlled laboratory experiments and long-term studies of natural populations have enabled scientists to observe and measure evolution as it occurs. b. false. All evolutionary changes are observable as they occur. c. true. Evolution is a theory and not a fact, and no one can observe a theory. d. true. Evolution is the change in allele frequencies in a population, and scientists cannot view the alleles; they can only infer the activity of evolution from observed phenotypic changes. e. true. Evolution occurs over thousands to millions of years; scientists can only infer its activity after the fact.

a. false. Multiple replicated, controlled laboratory experiments and long-term studies of natural populations have enabled scientists to observe and measure evolution as it occurs.

The longer two species have been evolving on their own, the greater the number of _____ that accumulate between them. a. genetic differences b. convergences c. genetic similarities d. homologous structures e. DNA bases

a. genetic differences

Which of the statements are characteristics of a good hypothesis? (2 answers) a. is based on previous research in the field b. relies heavily on cutting edge technology c. is able to be tested using validated techniques d. is developed from data that cannot be replicated e. is created using an idea based on a science fiction novel

a. is based on previous research in the field c. is able to be tested using validated techniques

For a population to evolve through natural selection: a. its members must possess inheritable variation. b. the mutation rate must be high. c. it must have a small population size. d. individuals must be migrating in and out of the population. e. it must be in a stable environment.

a. its members must possess inheritable variation.

Which factor defines a double-blind experimental design? a. neither the experimental subjects nor the experimenter knows which (if any) treatment the subjects are receiving. b. only the experimenter does not know which (if any) treatment the subjects are receiving. c. the subjects are randomly assigned into experimental and control groups. d. the experimenter does not influence the experiment's outcome. e. only the experimental subjects do not know which (if any) treatment they are receiving.

a. neither the experimental subjects nor the experimenter knows which (if any) treatment the subjects are receiving.

Julia wants to determine if temperature affects the growth of Escherichia coli (E. coli) bacteria. After preparing five Petri dishes with equal amounts of nutrient agar, Julia transfers one drop of E. coli broth culture into each Petri dish. As shown in the table, she places each Petri dish at a certain temperature. Julia measures and records the growth of the bacteria in each plate every day for two weeks. What is the independent variable in this example? a. the temperature b. the number of E. coli cultures c. the species of bacteria d. the amount of nutrient agar e. the length of time the bacteria are observed

a. the temperature

Which statement about biological literacy is true? a. Biological literacy is the ability to make conclusions from stories in the newspaper and information relayed by friends and family. b. Biological literacy is the ability to integrate ideas about biology into making wise decisions for oneself. c. Biological literacy is important for issues facing society but not as important for individuals. d. Assuming that all bacteria can infect you because your mother told you so is an example of biological literacy. e. Using the process of scientific inquiry to think creatively about real-world issues that have a biological aspect is not a component of biological literacy.

b. Biological literacy is the ability to integrate ideas about biology into making wise decisions for oneself.

In 1913, the chemist Niels Bohr suggested a model for the structure of the atom. He proposed that electrons travel around the nucleus in well‑defined orbits. He collected data of the atomic emission spectrum for the hydrogen atom and extended it to a model for other atoms. By 1925, scientists proposed a new kind of mechanics called quantum physics and more advanced research was conducted on atoms larger than hydrogen. New data and conclusions led to a more accurate model of electron motion. A new theory for the model of the atom was accepted, refining Bohr's model of the atom. Based on the history of the model of the atom, which statement about scientific theory is true? a. Not enough evidence supported Bohr's model, so it was a hypothesis rather than a theory. b. Further scientific results may be used to modify, dispute, or even falsify a theory. c. Scientific theories are proven wrong when new data and conclusions are revealed. d. Scientific ideas are judged democratically based on popularity.

b. Further scientific results may be used to modify, dispute, or even falsify a theory.

Which example describes the scientific method? a. a testable suggested explanation for a particular phenomenon or set of observations b. a defined set of steps by which scientists investigate natural phenomena or groups of observations to accurately explain how the natural world works c. an established explanation for a phenomenon or group of observations that is falsifiable and is well‑supported by evidence d. a specific design of experiments that includes a control group, an experimental group, a dependent variable, and an independent variable

b. a defined set of steps by which scientists investigate natural phenomena or groups of observations to accurately explain how the natural world works

When conducting a critical experiment to test whether taking echinacea reduces the duration or severity of a cold, which step is not important? a. providing some groups with treatments of longer duration than others b. exposing some groups, but not others, to the cold virus c. providing some groups with echinacea and others with a placebo d. exposing all of the volunteers to the cold virus e. randomly dividing volunteers into treatment groups

b. exposing some groups, but not others, to the cold virus

The descendants of a single finch-like species that arrived in Hawaii 4-5 million years ago are called: a. honey drippers. b. honeycreepers. c. parakeets. d. marsupials. e. Darwin's finches.

b. honeycreepers.

A null hypothesis: a. is a hypothesis that the experimenter hopes will be falsified. b. is the premise that no difference exists between a treatment and control group. c. is the result of an experiment that does not work. d. cannot be rejected. e. results from an improperly controlled experiment.

b. is the premise that no difference exists between a treatment and control group.

Most mutations are: a. beneficial or neutral to the organism in which the mutation takes place. b. random with respect to the environmental needs of the organism in which the mutation takes place. c. occurring more often now than in the past. d. accounted for by the Hardy-Weinberg equilibrium. e. responsible for gene flow.

b. random with respect to the environmental needs of the organism in which the mutation takes place.

Carlos wants to determine if the amount of fertilizer cilantro plants receive affects their vertical growth. In five numbered pots with the same amount and type of soil, Carlos plants a cilantro seed at the same depth. Each day, every cilantro plant receives the same amount of sunlight and water. As shown in the table, every plant receives a certain amount of fertilizer each day for ten weeks. Carlos measures and records the height of each cilantro plant every day. What is the dependent variable in this example? a. the amount of fertilizer b. the height of the cilantro plants c. the type of soil d. the amount of water e. the amount of sunlight

b. the height of the cilantro plants

The best measure of an organism's fitness is: a. how long it lives. b. the number of fertile offspring it produces. c. the amount of care it receives from its parents. d. the number of mutations it acquires in its lifetime. e. the amount of food the organism can take in.

b. the number of fertile offspring it produces.

Which of the following does not meet all the characteristics to be categorized as alive but is classified as alive by some biologists? a. archaebacteria b. viruses c. self-pollinating plants d. self-replicating crayfish e. fungi

b. viruses

________ is the study of living things. a. Agriculture b. Science c. Biology d. Research e. Psychology

c. Biology

Which statement best explains the observation that more autism cases exist now than in the past? a. The vaccine for measles, mumps, and rubella has been established as a significant cause of autism. b. Autism has been selected for in recent generations by natural selection. c. Doctors are more aware of the condition and have better techniques for diagnosing and reporting it. d. More parents neglect their children, which is a cause of autism, now than in the past. e. Autism is caused by a new mutation and has just shown up in the last few years.

c. Doctors are more aware of the condition and have better techniques for diagnosing and reporting it.

Which statement is not true about natural selection? a. Natural selection acts to eliminate deleterious alleles from the gene pool. b. Natural selection leads to evolutionary change. c. Natural selection preserves advantageous traits acquired during an individual's lifetime. d. Genetic variation must be present in a population for natural selection to act. e. Individuals that are better suited to the environment should, on average, contribute more offspring to the next generation.

c. Natural selection preserves advantageous traits acquired during an individual's lifetime.

Darwin's observations while traveling on the Beagle helped him develop which theory? a. The number of current species remains constant. b. Genes can mutate. c. Species might change over time. d. The Earth is about 6,000 years old. e. The Earth is mostly unchanging

c. Species might change over time.

In 2001, the journal Behavioral Ecology changed its policy for reviewing manuscripts submitted for publication. The journal had used a single‑blind process in which reviewers' identities were unknown but authors' identities were known. After 2001, the journal used a double‑blind process in which neither the reviewers' nor the authors' identities were known. Analysis of the papers published between 1997 and 2005 revealed a significant difference in the percentage of published papers with a female first author before and after 2001. Select the statement that summarizes the information described by the pie charts. a. Identification of the gender of the first author as female did not affect the likelihood of publication prior to 2001. b. The journal published a higher percentage of papers with female first authors when reviewers knew the gender of the author. c. The journal published a higher percentage of papers with female first authors when reviewers did not know the gender of the author. d. The double‑blind review process resulted in less bias against female authors than the single‑blind review process.

c. The journal published a higher percentage of papers with female first authors when reviewers did not know the gender of the author.

If your hypothesis is "Hair that is shaved grows back coarser and darker," what is your null hypothesis? a. There is no difference in the coarseness of hair that is shaved relative to hair that is not shaved. b. Hair that is taken off with a cream depilatory grows back coarser and darker. c. There is no difference in the coarseness or color of hair that is shaved relative to hair that is not shaved. d. Hair that is shaved grows back finer and lighter. e. There is no difference in the color of hair that is shaved relative to hair that is not shaved.

c. There is no difference in the coarseness or color of hair that is shaved relative to hair that is not shaved.

When conducting a scientific experiment, which factor is tested? a. an observation b. a null hypothesis c. a prediction d. a control e. a question

c. a prediction

The purpose of the experimentation phase of the scientific method is to: a. gather evidence to formulate a theory. b. make predictive, testable statements about observations. c. gather evidence to support or reject a hypothesis. d. formulate a null hypothesis. e. gather preliminary data from which a hypothesis can be made.

c. gather evidence to support or reject a hypothesis.

If evolution has occurred: a. the mean value for a trait has increased or decreased. b. the frequency of a physical trait in a population has changed. c. the allele frequencies in a population have changed. d. the individuals in a population have had differential reproductive success. e. one species has split into two distinct species.

c. the allele frequencies in a population have changed.

The graph shows data on the average beak size in finches (across multiple years). Based on this graph, what seems to happen as the climate gets drier? a. The average beak size of the finches remains the same. b. No discernible relationship exists between beak size and climate. c. Birds with smaller beaks are more plentiful. d. Birds with larger beaks survive and reproduce better than birds with smaller beaks. e. Birds with smaller beaks survive and reproduce better than birds with larger beaks.

d. Birds with larger beaks survive and reproduce better than birds with smaller beaks.

Which statement is the most reasonable testable prediction for the hypothesis: "All birds can fly"? a. Locate places in the world where flight would be advantageous and count the number of birds that live there. b. Observe all the birds outside your home for a week to see if they all can fly. c. Take a random sampling of five birds from around the world to verify that they can all fly. d. Examine the list of all known species of birds and determine if any species cannot fly. e. In a double-blind study, take a random sampling of 100 animals to see if they all can fly.

d. Examine the list of all known species of birds and determine if any species cannot fly.

While traveling around the world on the HMS Beagle, Charles Darwin made which of the following observations? a. Only the largest and most fit organisms tended to survive. b. The fossils of the Galápagos tortoises were distinctly different from any extant species. c. All the island species of finch were much larger and fitter than the mainland finches. d. Island species of finch closely resembled mainland finches. e. Organisms on islands tended to have fewer offspring.

d. Island species of finch closely resembled mainland finches.

Using the given starvation resistance curve for fruit flies, what is the maximum number of hours an individual fruit fly could survive without food after an experimenter has selected for starvation resistance on this population over thousands of generations? a. 50 hours b. 35 hours c. 20 hours d. Theoretically, there is no maximum number of hours. e. 60 hours

d. Theoretically, there is no maximum number of hours.

From the graph shown here, the strongest statement we can reasonably make is: a. having access to a textbook caused students to score better on the exam. b. students with no access to a textbook will not do well on an exam. c. if we give textbooks to all the students who did not have textbooks, they all would score between 95% and 100% on the next exam. d. a statistically significant positive correlation exists between having access to a textbook and scoring well on the exam. e. a statistically significant negative correlation exists between having access to a textbook and scoring well on the exam.

d. a statistically significant positive correlation exists between having access to a textbook and scoring well on the exam.

Which example describes a theory? a. a defined set of steps by which scientists investigate a natural phenomenon or group of observations to accurately explain how the natural world works b. a proposed explanation for a phenomenon that cannot be tested for supporting or falsifying evidence c. a testable suggested explanation for a particular phenomenon or set of observations d. an established explanation for a phenomenon or group of observations that is falsifiable and is well‑supported by evidence

d. an established explanation for a phenomenon or group of observations that is falsifiable and is well‑supported by evidence

A sand-colored mouse moves from its usual beach habitat to the darker brush habitat away from the beach, making it more visible to predators. This example illustrates that fitness: a. is defined by an organism's health and strength. b. depends only on an organism's reproductive success. c. is completely genetically based. d. depends, in part, on the environment in which an organism lives. e. is defined by an organism's ability to survive.

d. depends, in part, on the environment in which an organism lives.

In the steps of the scientific method, what is the process where a scientist writes down tentative explanations or statements about what he or she expects might happen under certain conditions? a. conclusions b. observations c. experimentation d. hypotheses formation e. theory formation

d. hypotheses formation

Thinking scientifically relies on: a. learning lists of facts. b. accepting statements of others as true. c. intuition. d. objective observation and experimentation. e. applying your preconceptions.

d. objective observation and experimentation.

In the laboratory, you see a fuzzy growth on some of the gels in your incubator. What is the name given to this step of the scientific method? a. theory b. law c. hypothesis d. observation e. experimentation

d. observation

A relationship that has been established based on a large amount of observational and experimental data is a(n): a. assumption. b. fact. c. hypothesis. d. conjecture. e. theory.

e. theory.